... ) Material: High quality carbon steel Class :4.8, 5.8, 6.8, GR.2, A307 2) Material :Alloy steel :20MnTiB ,40Cr ,42CrMo ... :8.8, 10.9,12.9 ,GR.2,GR.5,GR.8,A325-1,A490-1 ,GR.B7,GR.B7M3) Material :stainless steel :302 ,304 ... Class: A2-50 ,A4-50 , A2-70 ,A4-70 ,GR.B8,GR.B8MSurface Refine : Part galvanization ,Colorful galvanization ,Army green galvanization ,Black ...